274 FOSSIL REPTILES. 



appeared to indicate the existence of a particular and unknown 

 genus. 



In the forest of Tilgate, where Mr. Mantell collected the 

 bones of crocodile which we have noticed, were also found 

 some remains of emys by the same gentleman. One seemed 

 to have belonged to a part of the carapace, which was a little 

 concave ; the other is a portion of the anterior edge. The 

 first was found in a very fine ferrugineous sand, strongly 

 agglutinated : the other in an agglomeration of divers little 

 rolled stones, or gravel, partly agglutinated by the sand, and 

 partly by spathic infiltrations. 



The immense beds of soft sandstone, called by geologists 

 molasse, which fill all the lower parts of Switzerland, and again 

 appear over great spaces in the south of France and in 

 Hungary, are considered as well as the lignites and the other 

 subordinate beds which they contain, to be superior to the 

 chalk, and inferior, or perhaps, in some places, contemporane- 

 ous, to the coarse coquillaceous limestone, and some other more 

 recent tertiary strata. These strata are rich in fossil remains, 

 which belonged to the land, and to the fresh water, in croco- 

 diles, in trionyx, and in palseotheria. It is, therefore, not 

 surprising to find among them, in the same strata, the bones 

 of emydes. Fragments have been found in the quarries of La 

 Grave, which appeared to have belonged to very large species. 

 They corresponded in form to the analogous portions of the 

 buckler of the emys serrata, but many of them were three or four 

 times as thick. One of these fragments M. Cuvier supposes to 

 have come from an individual of more than three feet in length, 

 which is an uncommon size in the existing species of emys. 

 There was even found the head of a coracoid bone, which indi- 

 cated a still greater size in the individual to which it had 

 belonged. Similar fragments were found in the molasse of 

 Switzerland, near the town of Aarberg, but which seemed to 

 have rather more analogy with the emys of Europe. 



In the argillaceous formation of the Isle of Sheppey, which 

 is a continuation of the plastic argilla of the neighbourhood of 



